原发性肝癌根治性切除术后早期复发是影响患者长期疗效的主要障碍和当前科学研究的热点。前期工作中，我们通过对736例肝癌进行全基因组测序，外显子测序及靶向深度测序，筛选并证实WNK2体细胞突变或拷贝数缺失和肿瘤早期复发密切相关，提示患者预后不良。同时，体内外功能试验表明WNK2失活促进肝癌的侵袭和转移，并诱导肝癌细胞发生上皮-间质转化(EMT)。本课题拟首先证实WNK2体细胞突变在肝癌侵袭转移中的重要作用；然后筛选并鉴定WNK2的底物及磷酸化位点，进而挖掘WNK2参与调控肝癌细胞EMT的关键信号通路，并明确其在肝癌侵袭转移中的作用和机制；最后在肝癌临床样本中验证WNK2和底物磷酸化水平，关键信号通路分子的表达及EMT表型的相关性，并探讨和肿瘤早期复发及患者预后的关系。通过以上研究，明确肝癌早期复发关键基因WNK2调控EMT及其在肿瘤侵袭转移中的作用和机制，为探讨肝癌防治中新的干预靶点提供依据。

The high rate of early recurrence in HCC patients limits their long-term survival after curative resection and it is the current research hotspot. Through whole-genome sequencing, whole-exome sequencing, and deep targeted sequencing on 736 primary HCC samples, we have identified somatic mutation and copy number loss of WNK2 predict higher rates of early tumor recurrence and shorter overall survival. Meanwhile, biofunctional investigations revealed a tumor-suppressor role of WNK2: its inactivation promote tumor growth, invasion and metastasis, as well as induce epithelial-mesenchymal transition (EMT) in HCC cells. In this study, we firstly plan to confirm the role of WNK2 somatic mutation on HCC invasion and metastasis. Then, through screening and identifying the substrate of WNK2 and its phosphorylation site, we will investigate the key signaling pathway involved in regulating EMT of HCC cells and reveal its role and mechanism on HCC invasion and metastasis. Finally, using clinical HCC samples, we will determine the relationship between WNK2, WNK2 substrate phosphorylation level, the expression of key signaling pathway components and EMT phenotype, and evaluate their prognostic significance. Through the above research, we will determine the role and mechanism of WNK2-a key gene involved in tumor early recurrence, regulated EMT in the invasion and metastasis of HCC, and provide experimental evidence for exploring the new intervention targets on the metastasis and recurrence of HCC.